Cluster analysis of arterial involvement in Takayasu arteritis reveals symmetric extension of the lesions in paired arterial beds

Abstract

Objective. The determinants of vessel targeting are largely unknown in vasculitides. This study was undertaken to identify patterns of vascular involvement in Takayasu arteritis (TA), using objective classification of vascular beds. We postulated that cluster analysis could unveil preferential associations between vascular beds commonly affected by TA.Methods. Peripheral vascular Doppler, computed tomography angiography, and angio-magnetic resonance imaging data from 82 patients with TA (according to the American College of Rheumatology criteria) were studied between January 1995 and May 2006. Crossrelationships of involvement between 24 main arteries were assessed using the phi correlation coefficient. Identification of patterns of vascular involvement was performed using agglomerative hierarchical cluster analysis.Results. Data were obtained from 82 patients (68 women [82.9%] and 14 men [17.1%]). The median duration of followup was 5.1 years (range 1 month to 30 years). For 16 (80%) of 20 paired arteries, the highest correlation of involvement was observed with the contralateral artery. Conversely, disease extension was contiguous in the aorta. Cluster analysis further confirmed that all paired arterial beds, except for the internal and external carotid arteries, clustered with their contralateral counterpart and that the aortic arch, the descending thoracic aorta, and the abdominal aorta clustered together.Conclusion. Our findings reveal that TA lesions mostly develop in a symmetric manner in paired vascular territories and that disease extension is contiguous in the aorta. This may prove useful for improving the radiologic followup of patients with TA and for providing a pattern for further investigations focusing on the mechanisms of vessel specificity in vasculitides.Takayasu arteritis (TA) is a rare chronic vasculitis of unknown etiology predominantly affecting the aorta and its major division branches (1). Although originally believed to be a disease mostly affecting young women of Asian descent, TA is now well recognized in both sexes and in various ethnic groups worldwide (2). The natural history of vascular lesions in TA is not well understood. However, considering the high frequency of involvement of the left aortic arch branches, Ishikawa hypothesized that these lesions begin in the left subclavian artery and subsequently extend to other sites (3).While conventional angiography has long been the gold standard for the assessment of vascular involvement in TA, this imaging modality is now progressively replaced by computed tomography (CT) and magnetic resonance imaging (MRI) angiographies. These latter methods offer several advantages over conventional angiography, including their noninvasiveness and their capability of demonstrating both mural and luminal

Update on Takayasu's arteritis

“…Grayson et al demonstrated that among 6 different vasculitides, TAK has the highest rate of new, severe manifestation (ischemic, vascular) incidence (44%) [8]. Clinical features of "vascular symmetry'' in TAK are investigated in 2 separate studies from USA and France [26,27]. Cluster analysis revealed that TAK lesions mostly develop in a symmetric manner in paired vascular territories and disease extension is contiguous in the aorta.…”

The Efficacy of Tocilizumab for Takayasu Arteritis: Review of the Literatures

“…Corticosteroids are the mainstay of therapy for active TA and the classic approach has been prednisone 40 -60 mg/day (1 mg/kg/day) for about a month, and then reducing the dose by 2.5 -5 mg/week until 10 -20 mg/day is reached [23]. Maksimowicz-McKinnon et al reported 75 patients with TA in an American cohort and reported that glucocorticoids induced remission in about 60% of patients, but relapses occurred in the majority (>50%) of the patients during steroid taper.…”

“…Maksimowicz-McKinnon et al reported 75 patients with TA in an American cohort and reported that glucocorticoids induced remission in about 60% of patients, but relapses occurred in the majority (>50%) of the patients during steroid taper. Other studies also state that disease control with only prednisone is inadequate (≤20% patients), and nearly three fourths (66% -84%) need other immunosuppressive agents [23]- [25]. Another limitation for the glucocorticoid therapy is the adverse effects, meaning that additional medications to counteract the side effects of glucocorticoids may be necessary.…”

Takayasu Arteritis Presenting with Internal Carotid Artery Dissection

“…In Takayasu arteritis (TA), vessel wall thickening and stenosis are the most common findings, whereas aneurysmal dilatations occur less frequently [1,2] and arterial dissection is rare. Cerebral ischemia may occur in up to 16% of the patients with TA [3] and can be due to several mechanisms such as subclavian steal in the arm, vessel stenosis/occlusion and embolism from the aorta or the heart [4].…”

“…Extension of arteritis in TA seems to occur in a symmetric way to the paired vascular beds and contiguously in the aortic arch, brachiocephalic trunk and the aorta [1]. Iliac occlusion is an uncommon complication of TA [2,3].…”